This invention relates to devices for monitoring RF transmitters to detect the occurrence of faulty conditions and for automatically switching off the transmitter whenever such a faulty condition is detected. More particularly, the invention relates to such a device wherein an extremely fast switching capability is achieved, such as 25 microseconds.
Recent developments in communication technology have been accompanied by a need for high-speed RF transmitter monitoring systems. In fact, recent FCC regulations make RF transmission monitoring and supervision mandatory. Prior art devices for monitoring transmitter power, etc., have been capable of switching response times to up to 50 milliseconds, however, current requirements indicate a need for response times as fast as 25 microseconds.
The types of transmitters for which the device of the present invention is designed include radio repeater systems, such as are used in the two-way communication field, and in the more recent computer terminal systems for dissemination of printed line information. Such systems require condition monitors for driver outputs, final outputs, VSWR at various points, as well as tamper alarms, cooling water flow, air flow, standby power fall-off, etc.
The device of the present invention satisfies the requirements indicated above and affords other features and advantages heretofore not obtainable.